<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    .box{
      position: absolute;
      left: 0;
      right: 0;
      top: 0;
      bottom: 0;
      margin: auto;
      width: 10%;
      height: 0;
      padding-top: 20%;
      background-color:pink;
    }
  </style>
</head>
<body>
  <div class="box"></div>
</body>
</html>